Redshift distributions, n(z), of the galaxy samples. The lens sample is obtained from the KiDS-bright galaxies described in Bi21. The blue line shows n_sp(z), i.e. the redshift distribution of KiDS galaxies for which we have spectra from the GAMA survey. The red line shows n_ph(z), the distribution of the full KiDS-bright sample as estimated by ANNz2 with a photometric redshift cut of z_ph <  0.1. The black line shows our best-estimated n_be(z): a smoothed version of n_ph(z) that better accounts for photometric redshift errors. The cyan, orange, and brown lines show the third, fourth and fifth redshift bins of the KiDS-1000 data, as estimated in H21. As the third bin strongly overlaps the sources, it is excluded from the analysis.